The invention set forth in this specification pertains to new and improved roof flashing structures for use on a roof so as to form a seal around a pipe extending through the roof.
The term "flashing" is commonly utilized in the building trade to designate pieces of sheet metal or the like used to cover and protect various types of joints. Various different specific flashing structures are commonly utilized in covering and protecting different types of joints. Thus, for example, it has been commonplace to utilize flashing structures for covering and protecting joints between a roof and a vent pipe or the like which have been constructed so as to utilize a flat plate or sheet of material carrying an upstanding flange adapted to fit around the exterior of such a pipe. Normally the flange in such a structure is sealed to such a pipe by a calking type composition. At times such sealing compositions are referred to as mastics.
Specialized roof flashing structures as indicated in the preceding paragraph are commonly recognized to have certain limitations. Normally such structures can only be utilized with a roof located at a specific angle to a pipe extending through the roof. This is disadvantageous because it necessitates the maintenance of an inventory of different flashing structures for use with different roofs which are flat or are sloped at various different angles. Roof flashing structures as indicated are also considered disadvantageous because of the use of the compositions which are employed to form a seal between them and a pipe. In general such compositions tend to be somewhat messy, difficult and time consuming to apply. Further, such compositions will frequently tend to crack and/or deteriorate after prolonged use. This, of course, will result in either leakage or the possibility of leakage.